[tz] Issues with pre-1970 information in TZDB
eggert at cs.ucla.edu
Fri Sep 24 00:16:56 UTC 2021
On 9/22/21 15:23, Howard Hinnant via tz wrote:
> Before the change the tzdb does a “best effort” on pre-1970 dates.
No, quite the reverse. There are many places in 2021a where we have some
data (often unreliable) about pre-1970 timestamps, and we put that data
into 'backzone' instead of doing a "best effort" on pre-1970 dates in
the default database. Examples include Africa/Addis_Ababa,
Africa/Freetown, and Asia/Harbin. I expect that there are more Zones in
2021a where this sort of thing happens, than Zones in the changes being
There's a lot of precedent for the recent changes, and a lot of
experience for the fact that the fallout from this kind of change is
negligible in practice.
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